A kiln is heated to a temperature of 1030C and then allowed to cool. The temperature of the kiln, 0C, after t hours from when the kiln is allowed to cool is given by the formula 0 = 1030ekt where k is a constant. After 8 hours the temperature of the kiln is 637C. i. Show that the value of k is approximately -0.06 ii. Find the temperature after 13 hours. iii. Find the value of when t = 12. de dt [3] [2] [3]